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104 University of California Publications in Zoology [Vou. 30

Circus hudsonius (Linnaeus). Marsh Hawk

Found nowhere about Atlin during the breeding season. The first south-bound migrant appeared August 26; then, September 9 to 15, between Atlin and Lake Teslin, marsh hawks were seen in numbers flying southward. Last seen, near Atlin, September 21.

Accipiter velox (Wilson). Sharp-shinned Hawk

Seen at Skagway, May 21. Undoubtedly nests in the Atlin region, for occasional individuals were seen throughout the summer. Not common at any time, not even after the southward migration had begun. Last seen on August 29. One specimen collected, an immature male, August 18 (no. 44728).

Astur atricapillus atricapillus (Wilson). Eastern Goshawk

Undoubtedly nests in the Atlin region, probably in the lowlands, for individuals were seen at fairly frequent intervals throughout the summer. In August there was a noticeable increase in numbers, mostly of young birds, flying southward. Several immatures were shot but not preserved, and all were of the pale coloration that appears to be characteristic of the subspecies atricapillus. One specimen was skinned (no. 44729), a male in adult plumage, almost fully acquired, taken September 5. This bird is of interest in view of the argument advanced by Taverner (1916, p. 860; 1918, p. 216) that the goshawk molts from the streaked juvenal plumage into a coarsely barred stage (the sub- species striatulus) and later into the more finely barred plumage that is considered to be typical of the subspecies atricapillus.

The bird in question had just molted from the juvenal plumage. Very few juvenal feathers remain, but careful investigation before the bird was skinned showed enough old streaked feathers on various parts to demonstrate that this was the first assumption of adult plumage. This bird is pale colored and finely barred, as in atricapillus. Some of the breast feathers have rather broad mesial streaks but it is otherwise just like other specimens of atricapillus at hand, and very different from coastal examples of striatulus.

The status of the two forms atricapillus and striatulus cannot be regarded as settled, but the evidence at hand points to the existence of two such subspecies. Characteristic color differences occur in both